Quick wiring device



Aug. 22, 1961 s. A. MASON QUICK WIRING DEVICE Filed July 10, 1959INVENTOR Stuart A. Mason x9 NEY WZKSFQESE; Q @mMz. F F

Unite The present invention relates to electrical terminal devices whichare utilized to transfer electrical energy between conductors inelectrical networks.

A historical review of the development of terminal devices indicatesthat creative eifont has been directed toward providing terminal deviceshaving structures which are easily manufactured and which readily engageconductors when placed in use. This effort has been consistent withmarket requirements for cost reduction and contemporary demands forsimplicity in design and ease of operation of terminal devices.

The screwless-type terminal device is an outgrowth of this effort, andit is particularly characterized by the fact that it automaticallyengages and retains inserted conductors, such as those provided in theform of wires. Thus, simplicity is provided through this automaticfeature commonly termed rapid wiring. It is fundamental to note thatcertain physical principles control the mechanical relations betweencomponent structural elements in providing the rapid wiring feature inscrewless terminal devices associated with prior art mechanicalenvironments. In new mechanical environments for terminal devices,different mechanical relations exist so that different physicalprinciples or different combinations thereof must be inventively appliedto substantially different structural elements in order to provideadequately the rapid wiring feature. If, for example, the rapid wiringfeature is to be provided in a terminal device positioned in arel-atively limited space, buckling of the wire engaging members of theterminal device becomes a problem because the members are necessarilyminiaturized to satisfy space limitations.

It is, therefore, an object of the invention to provide an electricalterminal device having novel means for affording rapid electrical andmechanical engagement of a conductor.

It is another object of the invention to provide an electrical terminaldevice having novel means for affording rapid electrical and mechanicalengagement of a conductor and for affording ready release of theconductor.

It is a further object of the invention to provide an electricalterminal device having novel means for affording rapid electrical andmechanical engagement of a conductor so that any pull on the conductorresults in firmer engagement thereof through the influence of tensile reaction by the terminal device.

' These and other objects of the invention will be more apparent uponstudy of the following detailed description of an illustrativeembodiment of the invention as related to the accompanying drawings, inwhich:

FIGURE 1 is a top plan view of a screwless terminal device constructedin accordance with the principles of the invention;

FIG. 2 is -a longitudinal sectional view of the terminal device takenalong the reference line IIII of FIG. 1; FIG. 3 is an end view,partially in section, of the terminal device of FIG. 1;

FIG. 4 is a longitudinal sectional view of the terminal device takenalong the reference line II--II of FIG. 1, here with a conductor beingpartially inserted;

FIG. 5 is a longitudinal sectional view of the terminal device takenalong the reference line IIII of FIG. 1, here with the conductor beingfully inserted; and

States Patent 0 ice FIG. 6 is a longitudinal sectional view of theterminal device taken along the reference line 11-11 of FIG. 1illustrating a method for disengaging the fully inserted conductor.

In accordance with the broad principles of the invention, a screwlessterminal device is formed so that an in:

serted conductor is electrically and mechanically engaged.

by automatic action of the terminal. Any pull on the conductor isopposed by tensile reaction of the device causing firmer engagement ofthe conductor, but the conductor can be independently released throughthe use of a suitable instrument.

With reference to FIGS. 1, 2, and 3, a screwless terminal device 10 canform part of an electrical apparatus (not shown) and therein serve asmeans for transmitting electrical energy when conductively connectedwith conductors associated with electrical energy sinks or sources (notshown). The screwless terminal device 10 comprises a conductor receivingterminal lug 12 and a conductor engaging clip- 14, each of which can befabricated in accordance with ordinary manufacturing methods, such as bya stamping or a punching operation. As shown in FIG. 3, the lug 12 issupported above an insulating base 16 that is integral to theaforementioned electrical apparatus and by a pair of spacers 18 and issecured to the base 16 by screws 20. It is to be particularly noted thatthe lug 12 can be supported on the base 16 by other means. For example,a terminal device or member (not shown) can include an integral lug andbe formed so that, when the terminal member is clamped against a base,the integral lug is disposed in a position relative to this basesubstantially the same as the lug 12 is disposed relative to the base 16in FIG. 3. A more thorough description of this modification of theinvention is set forth in an application of S. A. Mason, filedconcurrently herewith, entitled Wiring Device, Serial Number 826,266 andassigned to the present assignee.

With further reference to FIGS. 1, 2 and 3, the lug 12 can be connectedto an electrically conductive portion of the aforementioned electricalapparatus through the use of clamping means, solder, or any othersuitable means. Although the base 16 can have any form whichparticularly adapts it for use in the parent electrical apparatus, it isshown in FIGS. 1 and 3 as having a slablike' form with a clip retainingridge 23, but with an otherwise generally flat surface 22 which providesfor frictional cooperation with the clip .14 in a manner to be describedmore fully. Additionally, openings (not shown) are provided in the base16 for reception of the screws 20.

The spacers 18 are stationed against the insulating base 16 in order tosupport the lug 12 in a position substantially parallel to, butseparated from, the base 16. As previously noted, the construction ofthe spacers 18 between the base 16 and the lug 12 is not critical, and,

, in fact, any structure that supports the lug 12 in a positionsubstantially parallel to, but separated from, the base 16 couldequivalently be employed provided the space between the lug 12 and thebase 16 remains free for reception of the clip 14.

The conductor receiving terminal lug 12 is preferably but notnecessarily T-shaped. A crossbar 24 is sup ported at its ends 26 by thespacers 18 and associated parts as previously described. A cantileverarm 28 is joined to a middle portion 30 of the crossbar 24 and issubstantially transverse thereto. An indentation is made along thelength of the arm 28 and across the cross-bar middle portion 30 so thatan aligned channel 32 exists for reception of a conductor. Additionally,a clip retaining tang 33 projects from the arm 28.

The conductor engaging clip 14, of a relatively hard material such asstainless steel but not limited thereto;

3 is generally rectangularly shaped. The clip 14 comprises side portions36, end portion 38 and an opposite end portion 40 with a tab 42, so thatan opening 44 is partially circumscribed by sharp curvilinear edges 50and 46 of the end portions 38 and 40, respectively, and otherwisecircumscribed by the clip side portions 36 to provide for slippage ofthe clip 44 onto the arm 28 of the lug 12.

Thus far the structure of elements usable with the invention has beendescribed, and it remains to set forth the cooperation of these elementsaccording to the principles of the invention. The size of the clip 14and the lug 12, respectively, is determined by the standard wire sizeswhich the terminal device 10 must engage and by the space in theaforementioned electrical apparatus in which the terminal device 10 mustfit. In any case, the lug arm 28 is supported substantially parallel tothe base surface 22, but it is separated therefrom, so that the clip endportion 38 necessarily glides angularly between the base surface 22 andthe lug arm 28 when the clip 14 is slipped onto the lug arm 28.

Once the clip 14 is fully inserted, an outer edge 48 of the end portion38 is stationed against the ridge 23 and the base 16 and the inner edge50 of the end portion 38 is stationed against the arm 28 and adjacentto, but separated from, the arm tang 33. Thus, the base ridge 23 and thearm tang 33 prevent, with the exception of tolerable limitations,funther inward and outward gliding motion of the clip 14 between thebase .16 and the arm 28 and therefore substantially retain the clip 14in its inserted position. The arm 28 of the lug 12 passes through theclip opening 44 so that a wire-engaging passage 52 is defined by thecontour of the arm channel 32 and the clip curvilinear edge 46.

As represented in FIGURE 4, a conductor or wire 54, upon being insertedinto the device 10 for engagement therewith, slides along the channel 32and through the passage 52 exerting a force on the sharp edge 46 of theclip 14. This force creates a counterclockwise moment on the clip 14, asviewed in FIG. 4, and, accordingly, causes tie clip 14 to rotate, and tobow slightly in instances where the resiliency of the clip material andthe thickness of the clip 14 allows the same, about its edge 48.Reactionary forces by the base 16 on the edge 48, by the arm 28 on theedge 50, and by the edge 46 on the conductor 54 create a net clockwisemoment that opposes the counterclockwise moment caused by the insertionof the wire 54. Rotation, and bowing in the previously mentionedspecific instances, of the clip 14 continues until the two opposingmoments equal each other so that a state of equilibrium exists for theclip 14. As a consequence of the rotation of the clip 14, the cantileverarm 28 is bent outwardly from the base .16 because added separationbetween the base 16 and the arm 28 is necessary to accommodate therotated clip end portion 38, but if the clip 14 is constructed so thatit also hows, the arm 28 will bend only nominally away from the base 16.The outward bending of the arm 28 and the tendency of the clip 14 toresume its original angular position causes the conductor 54 to bepressed more firmly against the sharp edge 46 of the clip 14. Thus, whenthe conductor 54 is fully inserted (-FIG. the terminal device 1! rigidlyengages the conductor electrioally and mechanically because the clipedge 46 then exerts a reactionary force which indents the conductor 54and binds the same against the lug arm 28.

When the conductor 54 is pulled along arrow 56 in FIG. 5, a force in thedirection of the arrow 56 is exerted on the clip edge 46. In accordancewith well-established principles of mechanics, this force can beresolved into a component that acts longitudinally along the plane ofthe clip 14 and one that acts transversely to the plane of the clip 14.The transversely resolved force creates a clockwise moment which acts torotate the clip 14 in a clockwise direction and to alleviate, in thementioned specific instances, any prior counterclockwise bowing in theclip 14, thereby further identing and more firmly engaging the conductor54. The longitudinally resolved force causes tensile stress in the clip14 so that it cannot fail by buckling as it could if pull on theconductor 54 caused compressive stress in the clip 14.

FIG. 6 depicts a method that is used to release the conductor 54 fromthe terminal device 10. Any relatively blunt-edged instrument 56, suchas a screwdriver, can be pressed against the tab 42 until the clip 14bends sufiiciently in a counterclockwise direction so that the clipcurvilinear portion 46 is released from engagement with the conductor54.

The terminal device described herein can be modified in numerous wayswithout departing from the broad principles of the invention.Accordingly, it is desired that the invention be not limited in scope tothe embodiment and modifications thereof described, but that theinvention be accorded an interpretation consistent with the scope andspirit of its broad principles.

What is claimed is:

1. An electrical terminal arrangement comprising a base having aprojecting ridge, at least one spacing member positioned against saidbase, a conductive lug having a cantilever arm with a projecting tangand having a channel for receiving a conductor, said lug being supportedon said spacing member thereby separating said cantilever arm from saidbase, and an elongated clip having an opening through which said lug armis extended, said clip including an end portion that is positioned atone extremity against said base and adjacently of said base ridge and atits opposite extremity adjacently of said clip opening against said lugarm and adjacently of said lug arm tang to restrain said clip fromsubstantial movement along said lug arm, the spacing of said lug armfrom said base and the location of said clip opening being so providedas to require said clip to extend angularly relative to said lug arm,said lug arm channel and said clip opening defining a passage throughwhich said conductor can be passed causing said clip to deflect relativeto said lug arm sufficiently to clamp mechanically and electrically saidconductor against said lug arm, said clip responding in tension towithdrawal forces on said conductor resulting in a more firm engagementof said conductor, said clip additionally having an opposite end portionenabling said conductor to be released when said opposite end portion ispressed away from said conductor.

2. An electrical terminal device being positioned when used above a basesurface, said device comprising a conductive lug having a trough portionfor receiving a conductor, and an elongated clip having one endpositioned on said base surface and having an opening, said troughportion extending through said clip opening, said clip opening being solocated and said trough portion being so spaced from said base surfaceas to require said clip to be eX- tended angularly relative to saidtrough portion, said trough portion and said clip thus defining apassage through which said conductor can be passed causing said clip todeflect relative to said trough portion through one of unitary pivotalmovement and bowing movement and a combination of these movementssufliciently to clamp electrically and mechanically said conductoragainst said trough portion, said clip responding in tension to restraindisengagement of said conductor.

3. An electrical terminal device being positioned when used above a basesurface, said device comprising a conductive lug having an arm forreceiving a conductor, an elongated clip having an opening through whichsaid arm is extended and having one end against said base surface, saidclip opening being so located and said arm being so spaced from saidbase surface as to require said clip to be extended angularly relativeto said arm, said arm and said clip defining a passage through whichsaid conductor can be passed causing said clip to deflect relative tosaid arm through one of unitary pivotal movement and bowing movement anda combination of these movements sufliciently to clamp electrically andmechanically said conductor against said am, said clip responding intension to restrain disengagement of said conductor, and means formingpart of said clip for relaxing the clamping action on said conductorupon actuation by external cooperating means so as to release saidconductor.

4. An electrical terminal device being positioned when used above a basesurface, said device comprising a conductive lug having a cantilever armfor receiving a conductor, and an elongated clip having side and endportions circumscribing an opening with one of said clip end portionsbeing located between said base surface and said arm, said arm extendingthrough said clip opening, said end portion being so sized and said armbeing so spaced from said base surface as to require said clip to extendangularly of said arm, said arm and said clip defining a passage throughwhich said conductor can be passed to be engaged by said arm and by saidclip which deflects relative to said arm through one of unitary pivotalmovement and bowing movement and a combination of these movements, saidclip being responsive in tension to engage the conductor more firmlywhen a withdrawal force is exercised on the conductor, the other of saidclip end portions enabling said conductor to be released when said otherend portion is forced away from the conductor.

5. An electrical terminal device being positioned when used above a basesurface, said device comprising a resilient conductive trough portionfor receiving a conductor, and an elongated clip having one endpositioned on said base surface and having an opening through which saidtrough portion extends to provide a conductor receiving orifice boundedby the periphery defined by a transverse section of said trough portionand by an edge portion of said clip adjacent said clip opening, meansfor supporting said trough portion relative to said base surface and fornormally holding said clip in angular relation to said trough portion,said clip deflecting relative to said trough portion and engaging saidtrough portion to force said trough portion away from said base surfaceas a cantilever when said conductor is passed through said orifice, saidorifice boundary portions thereby being enabled to engage saidconductor.

6. An electrical terminal device being positioned when used above a basesurface, said device comprising a conductive lug having a conductorengaging portion, a clip having an opening through which said conductorengaging portion extends, means for supporting said lug and said cliprelative to said base and for enabling said clip to be positionedangularly relative to said conductor engaging portion, said clipdeflecting relative to said conductor engaging portion through one ofunitary pivotal movement and bowing movement and a combination of thesemovements when a conductor is passed through said clip opening to beclamped against said conductor engaging portion.

7. An electrical terminal device being positioned when used above a basesurface, said device comprising a conductive lug having a conductorengaging portion, a clip having an opening through which said conductorengaging portion extends, means for supporting said lug and said cliprelative to said base and for enabling said clip to be positionedangularly relative to said conductor engaging portion, said clipdeflecting relative to said conductor engaging portion through one ofunitary pivotal movement and bowing movement and a combination of thesemovements when a conductor is passed through said clip opening to beclamped against said conductor or engaging portion, and said conductorengaging portion being deflected outwardly against said conductor inresponse to the deflection of said clip so as to enhance the clampingaction.

8. An electrical terminal device being positioned when used above a basesurface, said device comprising a conductive lug having a conductorengaging portion, a clip having an opening through which said conductorengaging portion extends, means for supporting said lug and said cliprelative to said base and for enabling said clip to be positionedangularly relative to said conductor engaging portion, said clipdeflecting relative to said conductor engaging portion through one ofunitary pivotal movement and bowing movement and a combination of thesemovements when a conductor is passed through said clip opening to beclamped against said conductor engaging portion, said supporting meansincluding a projection on said conductor engaging portion engageablewith said clip so as to preclude withdrawal of said clip over saidconductor engaging portion.

9. An electrical terminal device being positioned when used above a basesurface, said device comprising a conductive lug having a conductorengaging portion, a clip having an opening through which said conductorengaging portion extends, means for supporting said lug and cliprelative to said base and for enabling said clip to be positionedangularly relative to said conductor engaging portion, said clipdeflecting relative to said conductor engaging portion through one ofunitary pivotal movements and bowing movement and a combination of thesemovements when a conductor is passed through said clip opening to beclamped against said conductor engaging portion, and said clip beingtensed when withdrawal movcment of said conductor is attempted.

References Cited in the file of this patent UNITED STATES PATENTS

